【初中英语知识】:助动词的用法

发布时间:2020-12-23 19:26:12 阅读数:
摘要: 常见的助动词有:do、be、have,它们的用法各不相同,常见用法如下:...

   常见的助动词有:do、be、have,它们的用法各不相同,常见用法如下:

初中英语,助动词的用法

  一、be的用法

  1.be+动词不定式to do。

  ①表示最近、未来的计划或者安排。

  Eg. He is to go to England next week.

  ②表示命令。

  Eg. You are to explain this.

  ③表示征求意见。

  Who is to go there?

  ④表示约定。

  Eg. We are to meet at the school gate.

  2.be+现在分词,构成进行时态。

  Eg. They are having a class.

  3.be+过去分词,构成被动语态。

  The window was broken by Mary.

  二、do的用法

  1.构成一般疑问句。

  Eg. Do you want to pass the exam?

  2.do + not 构成否定句。

  Eg. He doesn't like to study.

  3.构成否定祈使句。

  Eg. Don't go there.

  4.放在动词原形前,用来加强该动词的语气。

  Eg. I do miss you. 我真的想你。

  5.用于倒装句。

  Eg. Never did I hear of such a thing.

  注意: 引导此类倒装句的副词有never、seldom、rarely、little、only、 so、well等。

  三、have的用法

  1.have +过去分词,表示完成。

  Eg. By the end of last month, they had finished half of their work.

  2.have + been +现在分词,构成完成进行时,即现在完成时。

  Eg. I have been studying English for ten years.

  3.have+been +过去分词,构成完成时态的被动语态。

  Eg. English has been taught in China for many years.